1. Field of the Invention
The present invention relates to a fan control method for cooling a computer system.
2. Background of the Related Art
Computer systems typically include a number of electronic components disposed within a chassis. These components generate heat as a byproduct of electrical power consumption, and require a cooling system to prevent the components from overheating and experiencing thermal damage. A common cooling system includes one or more fans for inducing airflow through the chassis across the electronic components. For example, a personal computer (PC) or server may include one or more onboard fans provided inside the chassis of the PC or server. In larger computer systems, such as in a rack-mounted computer system, a shared blower module having one or more fans may be provided in a chassis for cooling multiple servers mounted in a common chassis. For larger computer systems, such as in a datacenter, a more comprehensive cooling system may include a dedicated computer room having specialized HVAC equipment and a particular arrangement of racks that includes alternating hot and cold aisles.
The large, high-speed fans and blower modules used for cooling servers and other information technology equipment are the primary source of noise in a datacenter. A datacenter typically includes many densely-packaged rack-mounted servers and many fans. The combined noise of the many fans and blower modules in a datacenter produce an undesirable level of noise. Additionally, the many fans and blower modules in a datacenter contribute significantly to the power consumption of the datacenter. Unfortunately, limiting or reducing the amount of airflow through the computer system can require reducing the load on a processor, which causes the computer to run at less than its full processing capacity. In order to allow such large computer systems to operate at full processing capacity or performance, the data center may be physically separated from office spaces to reduce the noise and discomfort experienced by employees. Policies may also require noise levels to be reduced below prescribed limits whenever a person is in the data center.